4 posts tagged with "ot-security"

Industrial security used to mean padlocking the control room and keeping the plant network air-gapped. Those days ended the moment someone plugged a cellular gateway into the PLC cabinet. Now every edge device streaming telemetry to the cloud is an attack surface — and the cryptominer that quietly hijacked your VM last month was the gentle reminder.

This guide covers the practical security mechanisms you need to protect industrial data in transit — MQTT over TLS, certificate management for OPC-UA and cloud brokers, SAS token lifecycle, network segmentation patterns, and what zero-trust actually means when your "users" are PLC gateways running on ARM processors with 256MB of RAM.

There's a persistent myth in manufacturing that "air-gapped" OT networks don't need security. The moment you connect a PLC to an edge gateway that publishes data to the cloud via MQTT, that air gap is gone. You've built a bridge between your operational technology and the internet, and every decision you make about that bridge — TLS configuration, certificate management, authentication, network architecture — determines whether you've built a secure connection or an open door.

This guide covers the practical security decisions for IIoT deployments, based on hard-won experience connecting industrial equipment in environments where a misconfiguration doesn't just leak data — it can affect physical processes.

Here's a uncomfortable truth from the field: most industrial IoT deployments I've seen have at least one Modbus TCP device exposed without any authentication. No TLS. No access control. Just port 502, wide open, on a "segmented" network that's one misconfigured switch from the corporate LAN.

The excuse is always the same: "It's air-gapped." It never actually is.

This guide covers what securing industrial protocol communications looks like in practice — not the compliance checkbox version, but the engineering decisions that determine whether an attacker who lands on your OT network can read holding registers, inject false sensor data, or shut down a production line.

In December 2023, a water treatment facility in Aliquippa, Pennsylvania was hacked through an internet-exposed Unitronics PLC. The attackers — linked to an Iranian state group — gained access because the PLC was connected directly to the internet with default credentials. The incident didn't cause physical harm, but it demonstrated a truth that manufacturing CISOs have been warning about for years: the convergence of IT and OT networks creates attack surfaces that most industrial organizations aren't prepared to defend.